System of electrical distribution.



- S. FERGUSON.-

SYSTEM OF ELECTRICAL DISTRIBUTION. APPLICATION FILED JULY 13, 1903.

Patented July 7, 1914.

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- 1 samuelFrguson,

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' s. FERGUSON, SYSTEM OF ELECTRICAL DISTRIBUTION. APPLICATION rILn'n JULY 1a, 1903 Patented July 7, 1911 6 SHEETS-SHEET 2.

S. FERGUSON.- SYSTEM OF ELECTRICAL DISTRIBUTION.

APPLICATION FILED JULY 13, 1903.

Patented July 7, 191;

6 BIIBETS-SHBET 3.

Inventor: Samuel Ferguson,

' fIULy.

S. FERGUSON.

SYSTEM OF ELECTRICAL DISTRIBUTION.

mm. m w m m w n ma m a P 7 APPLICATION FILED JULY 13, 1903. 1 1 03,0 1 8.

Inventor: Samuel Ferguson, by

s. FERGUSON. SYSTEM OF ELECTRICAL DISTRIBUTION.

1,103,018. APPLICATION FILED J'ULY13, 1903. Patented July-7,

5 SHEETS-SHEET 5.

\Z'i/nesses: I 15% Inventor: Samuel Ferg uson. y y.

UNITED STATES PATENT OFFICE.

SAMUEL FERGUSON,

OI SCHENECTADY, NEW YORK, ASSIGNOR 'IO. GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

SYS'I'EM OF ELECTRICAL DISTRIBUTION.

Specification o1 Iietters Patent.

Patented Jul 7, 1914.

Applicationfiled July 13, 1903. Serial No. 165,201.

To all whom, it may concern:

Be it known that I, SAMUEL FERGUSON, a citizen of the United States, residing at Schenectady, county of Schenectady, Stateof New York, have invented certain new and useful Improvements in Systems of Electrical Distribution, of which the followsingle rectifierfor example is in' per-ation',

- the attempt to throw another r ct-ifier in by thisitroubleis done awaywithg 7 3:;

' connecting the same in circuit.

multiple with it causes the rectifier already in circuit to cease, operations as soon as the second rectifier starts. In accordance with my invention I have provided means where- In one form of rectifier 'toywhichmy vention is applicable, inductance coils-are .actance' coils as distinguished from the arused for storing and restoringenergy, so as to maintain a continuous How of current in the rectifier and therefore enable it to oper-- ate, and so also asto cause both polarity waves of the alternating current to be rect-ified instead of waves of one polarity only. In rectifiers of this character, the inductance coils have heretofore been made with sepa- I rate cores. In accordance with one feature of my invention, a single core "for the inductance coils may be used thereby securing various advantages such as economy of space, economy of material, and so forth.

My invention further" comprises certain other. details both as to the construction of the apparatus and also as to the mode The. -novel features which I believe are characteristic of my in ention I have pointed 'bufiwith particularity in the appended p The invention: itself, however, as to L l eonstructionfand mode of operabetter understood by reference tthe foliowingdescription which is to be taken in connection with the accompanying drawlngs, in which Figure 1 is a perspective view of a single tem of distribution in' which a plurality of rectifiers are operated from a single set of inductance coils and are arran ed with their rectified circuits as well as their alternating current terminals in multiple with each other. Fig. 4 is amodification of the afrangement of inductance coils shown in Fig.

3.' Fig. 5 represents a plurality of vapor electric lainps, as distinguished from vapor rectifiers, cooperatively related to a single set of inductance. coils. Fig. 6 showsa plurality of rectifiers each rovided withits own set of inductance co' s but with their rectified circuits connected in multiple'with each other in accordance with one feature of.

Fig. 7 is a slight modificamy invention. tion ofthe' invention shown in Fig. 6. Fig. 8 shows my invention'as embodied in a system in which a plurality of multi hase rectifiers' are connected inmultiple with each other.

Fig. 9 represents .a system of multiple-connected three-phase rectifiers in which each rectifier is provided with; its own set of rerangement shown in Fig. 8 in which all of i-thelrectifiers are cooperativelyrelated to 'a.

single' .set ofreactance coils. Fig. 10 shows my invention as applied to rectifiers of a type'difl'erent ,II'OIII those shown in preced- 5 ing figures of the drawings.

In Fig. 1 the rectifier isshown as mounted on a: base 1 of slate or other suitable material and provided with a perforated metallic protecting-casing 2 having a glass cover which from its nature can not be clearly shown in the drawings. The rectifier proper is indicated at 3 and is detachably secured by asbestos-lined clips 4, 5 and 6 to a pivotally-mounted support 7. This support 7 consists of a convenientlyshaped metal plate pivoted at 8 to-the base 1 and provided with a handle 9 by which it may be rocked about its pivot. The individual rectifier, except as to a certain feature to be mentioned, is not of my invention and therefore requires no elaborate description. In general the rectifiei' consists of a highly exhausted envelop terial. These electrodes are supported in position by glass-incased wires 17, 18 connected to leading-in wires .19 and 20. The graphite electrodes 15 and 16 constitute the two main anodes of the. rectifier and the large body of mercury 11 the cathode. The mercury electrode 12 is a starting electrode. It may be maintained permanently in circuit or if. desired may be automatically cut out when the rectifier starts. If the starting electrode is to be out out of circuit I may make use of the cut-out indicated at 21 in Fig. 1 in which it is shown as carried by the pivoted'plate 7. By mounting the cut-out as shown its weight lends stability to the pivoted member of the rectifier ,while at the same timeits presence in juxtaposition to the rectifier enables the abolition of a number of flexible conductors which would otherwise be necessary to connect the movable member of the rectifier with the cut-out if the latter were secured to the fixedbase of the apparatus. The various bindingposts serve the'useful purpose of taking the.

strain off of the leading-in wires of the rectifiers. The-cutout shown in Fig. l in per screw 24, and the second one movable, and

carrying a contact point 25 coiiperating with an adjustable contact point 26.." These two contact points are normally heldv together by means of a compressionrspring 27 which 'urges apart the two core pieces 22 and 23. The force of the spring ;is adjusted by the screw 24:- .Current is conveyed to. the movable contact 25 by means of the flexible conductor 28 operate only when the current reaches a cer tain' predetermined-value and will remain open whenjhe. current is, below that value.

In furtheranceoithis end an ironring '29. surrounds the' end of the core 23 when the.

contacts 25 and 26 are together. The-current in the exciting coil therefore must rise to a considerable value before the attraction of the "solenoid is' such as to withdraw the core from the attractive influence of the iron ring 29 and against the opposing iorce'of thejspring 27 When this withdrawal how; ever as once taken place and the core 23 is out of the-influence of the iron ring 29,-a-nd The cut-outds' intended to within proximity to .theother portion 22 of the core, a relatively small amount of current sufiices to hold the parts in this position, whence-it will be seen that the current through the solenoid may decrease largely in amount below that necessary to separate. thecontacts 25 and 26, before the contacts can again be closed by the action 'of the spring 27. This allows the cut-out to open the starting circuit only when it is certain that the rectifier has started and causes the starting circuit to close only when the cur- IBIItdI lQthQ I'GOtlfiBI either ceases entirely or is abnormally small.

In connecting up the} rectifier shown in Fig. 1, the two electrodes 15 and 16 are connected respectively to leads extending from a source of alternating current. Across these leads two'inductan'ce L coils are connected in series and the junction between them connected through a suitable consump- 'tion circuit with the main mercury electrode ing the rectifier on its support as indicatedin Fig. 1, a' circuitfis established which, as the-mercury separates, starts an arc which inturn causes arcs to'start between the-main mercury electrode 11. and the two upper trode permits only a small current to flow, the electrode may remain in circuit without other disadvantage than the slight loss of energy, in the resistance.

Rectifiers of, the character above described reactances, but as shown in Fig. 3 these reactances may, if desired, be arranged with have heretofore been provided'with separate 7 I their windings on the same core. This core,

which- I have indicated at 30, is provided.

with three'parallel legs connected by end piecesfi." On the'outer legsare mounted the windings 31 and 32whichare connected in nect-ions' arev such that the middle leg 65 of the-core forms a return ma etic circuit ;for"t-the fluxes developed by t e; two coils; Any-number of rectifiers, within the ca .Ea ity of the inductance coils, may be fed series with each other-across the alternating current supply mains '33 and 34. The cony .cotiperative connections to. the inductance .coils." If the rectified-{current "from-.each' rectifier has a separate circuit of'itsown no {special precautions areneceSSa'ry but if it a {is desired-that the rectifiers shou d be con- I nected; in multiple. on their direct Tcurrent. ',sides to acommon load, then I have f onnd.

- stantially the same form as that shown in Fig. 1 and, like the arrangement shown in this figure, provided with electrodes and otherwise of similar construction. In connecting up the rectifiers the two upper electrodes, as for example 41 and 42 of the rectifier 36, may be connected directly to the supply mains 33 and 34. I have found, however, that in case the voltage of the supply main is not of exactly the value to give the desired direct current voltage in the rectified'circuit, the inductance coils 31 and 32 may. perform the dual function of varying the voltage on the rectifier and of storing and restoring energy to maintain the rectifier in its characteristic mode of opera tion, the nature of which latter function it is unnecessary for me to enter into inasmuch as the rectifier, in its broader aspects, is not of my invention. For the purpose then of conveniently varying the alternating voltage on the rectifier bus-bars or conductors 43 and 44, I may connect these conductors by means of a switching device 45 which operates, as will be evident by an inspection of the drawings, to shift the connections of the conductors 43 simultaneously along'corresponding points in the windings of the inductance coils 31 and 32 toward or away from the terminals connected to the main supply leads 33 and 34. The connection is similar to a compensator with voltage ,adjusting taps. Each of the rectifiers 37 to 40 inclusive is connected to the bus-bars 43 and 44 in the same way as the rectifier 36. The main mercury electrode of each of the rectifiers is connected through a consumption circuit.to a lead 46 extending-to the junction between the two inductance' coils '31 and 32. Each of the rectifiers may as.

before mentioned have its own consumption circuit but if on.the other hand it is desired that the rectifiers should supply a c01nmon load, as for example that represented by the various translating devices comprised between the conductors 47 and 48, then the connection of each of the main mercury electrodes of the rectifiers must be made, to the. load through what I may term a steadying de'vicelwhich mayconsist of an inductance or a resistance. In Fig. 3, however, I have represented the respective rectifiers as provided withsteadying devices consisting of reactances 49 to 53 respectively, rather than resistances. The reactance'49 is indicated for example as havingan open mag netic. circuit, while the other reactances are provided with cores having closed magnetic circuits.

In starting into operation the system shown in .Fig. 3 the rectifiers may be started one after the other. A description of the starting of one will therefore sufiice for all.

Referring more particularly to the rectifier 36 it will be noted that at the bottom portion ,ofthe envelop are two mercury electrodes 54 and 55 to correspond respectively to the electrodes 11 and 12 in Fig. 1. The

electrode 54 is the main electrode from which the rectified current is' derived and is connected directly'to the circuit including the steadying device 49. The additional or starting electrode 55 is connected through a resistance or inductance 56 to one of the alternating current supply leads as for example the lead 57. In starting the rectifier the switch 58 is thrown so as to connect the direct current circuit of the rectifierthrough a starting resistance 59 to the lead 46 ex; tending back to the inductance coils 31 and 32. When the starting arc in the rectifier is sprung by rocking the rectifier, or otherwise bringing the mercury of the two electrodes 54 and 55 into momentary contact, the main arcs between the electrode 54 and the two upper electrodes 41 and 42 immediately follow and the rectifier'is in operation. \Vhen this is done the switch 58 may be thrown into the position indicated in Fig. 3 thereby connecting the rectifier directly across the circuit of the load. This operation may, however, be deferred until all of the recti-.

fiers have been started into operation through their respective starting resistances. In the case of the rectifiers 38 and 39, a common starting resistance 60 is used to start both rectifiers." If desired, a single starting resistance might be used for starting the entire set of rectifiers, one after the other.

In connection with the description of the rectifier 36, it has been assumed that the starting circuit including the resistance 56 remains closed during the operation of the rectifier:' The current in the starting circuit isfunidirectional and, inasmuch as it flows through the load, is not lost. There is, however, a certain though not considerable loss of energy in the resistance 56. To do away with this the cut-out heretofore described may be used, as diagrammatically indicated for example in connection with the rectifier 40. In this case the winding 61 of the cutout, which corresponds to the winding 21 in the two contacts 62 and 63 in the circuit of the. starting electrode. These contacts 62 and 63 correspond to the contacts 25 and 26 in Fig. 2 while-the startingelectrode 64 in Fig. 3 corresponds to the starting electrode 12 in Fig. 1. The connections of the cut-out just described, represent the connections of Fig. 1, is connected in the direct current cir cuit'of the rectifier and operates to separate however, the rectifiers may each be provided s'umption circuit represented by the mains 7 5 Figs. 1 and 2. I In Fig. 3 the taps in the windings of the A inductance coils 31 and 32-are so brought out w and the connections to the supply mains 33 words to step up the voltage, then the conmains. When, however, the switch is turned of the rectifiers 67, 68 and 69 is connected 77, 78- and 79. The other main 75 isconnected-with the rectifiers in each'instance by ltheirzjsteii'dying devices in this instance conthe cut-out which i s shown in detail views in and 34 and the rectifier bus bars 43 andi44 so made that the voltage on the bus bars may be made equal to orless than. that on the su ply mains 33 and 34. If it is desired to ma e the voltage on the busbars greater than that on the supply mains, or 1n other nections may bealtered as shown in Fig. 4, which differs from the corresponding portion of Fig. 3 in that a portion of each inductance coil, as at and 66 is reversed with respect to the remainder of the inductance coils while thevconnections to the'supply mains 33 and 34 are made so as to in clude all the coils in series. When the switch 45 is placed so as to connect the bus bars 43 and 44 to the supply mains 33 and 34, the voltage is the sameon the two sets of so as to move the leads or busbars 43 and 44 farther from the main lines 33 and 34 thus insertin one or more of the coil sections 65 and 66 etween themains and the rectifier circuit, the voltage on the rectifier will be increased above that of the mains according to the number of sections soinserted, the voltage of each being added to thatof the source of supply. 1 B

In'the arrangement shown in Fig. 3, the rectifiers are show-n. connected in multiple on their direct cii'rrent ends and with their. alternating current leads in multiple across a single set of inductance coils. If desired,

with its o wn set of inductance coils as indicated by way of illustration in Fig. 6. Each with the alternating current supply mains 70 and 71 and each is provided'with its own set of inductance coils as indicated at 72, 73 and74. The common loadsupplied by the rectifiers is indicated by translating devices of any desired character joined to the conand 76. One of these mains, as for example the main 76., is connected by a suitable lead, as. indicated, to the junctions between the inductance coils of each'set .72, 73 and 74, the points of connection being indicated at a lead including'a ste'adyingdevice. These leads are indicated at "80, '81 and 82 and sist of, inductance coils represented'at 83, 84- and 85. i" The. rectifiers shown in Fig. rovided 'jjgith starting devices,

sary.

to these features in Fig. 6 is deemed neces-' The arrangement shown in Fig. 7 is essentially the same as that shown in Fig. 6 except, owever, that the steadying devices 86 and 87 are formed respectively of resistances instead ofinductances as at 83 in Fig. 6.

z Theforegoing description has been limited to the consideration of vapor rectifiers. My invention, however, rendersit possibie, from a single set of reactance coils, to accomplish multiple operation of vapor electric lamps of a type resembling the rectifiers. Thus in Fig. 5 are shown a plurality of alternating current lamps 88, 89 and 90 supplied from the alternating current leads 91 and 92, to which a single set of inductance coils 93. 94 is connected. This set of inductance coils is similar to the set shown in Fig. 3 except. that for convenience of illustration it is shown as unprovided with voltage adjusting means which, in the case of lamps, would not ordinarily, be necessary. The lamps shown are all of the same type so that a description of one will therefore suffice for all. Referring then to the lamp 88 it will be seen to consist of an exhausted envelop of suitable length provided at the top with an enlargement so as to accommodate the electrodes 95 and 96, of artificial graphite or other suitable material, and provided at the bottom with adjacent pockets for containin bodies of Inercury or other vaporiza le material 97, 98 and 99 constituting electrodes. The middle electrode 98 is a main electrode which when the lamp is operating coiiperates with the two upper main electrodes 95, 96. The two electrodes 97 and 99 on either side of the electrode 98 are starting electrodes. The lamp is put in circuit'by connecting the uppereleotrodes 95 and 96 across the alternating current supply mains 91 and 92, whileat thefsame time a circuit is extended from the lower main electrode 98 to the junction 100 between the two inductance coils 93-and 94. In order to start up the lamp, the starting electrodes 97 and 99 are connected across the supply mains 91 and 92, with current'limitingdevices such as resistanc'es or inductances 101 and 102 in their circuits as shown. By shaking the lower end of the lamp or by other means causing the mercury ofthe two starting electrodes i104 whereupon the arcs desertth e. starting electrodes and pass to the main electrodes 95, 9e.

In order that the lamps shall run together in multiple fr'om the same reactance coils, 'a steadying device, such as an inductance or resistance, is connected in circuit with each in a manner similar to the connection of such devices ii the circuits of the rectifiers as heretofore escribed. Thus the steadying device for the lamp 88-is indicated at 105 while for the other lamps steadyingdevices are indicated at 106 and 107 The circuits of the respective lamps, after passing through the respective steadying devices are connected to the common conductor which extends to the junction 100 of the reactance coils.

The .foregoing description has been con fined more especially to an explanation of some of the applications of my invention to apparatus adapted for the-use ofsingle ply .mains.

number of three-phase rectifiers, three of' which are indicated at' 111, 112 and 113. These rectifiers resemble the single phase rectifiers already described except for the difference that instead oftwo; cylindrical electrodes contained in the 'enlar'ged portion of the envelop, I provide three to corre spond'in number with the number of sup- Thus inthe rectifier 111' the three electrodes are indicated at 114, 115 and y 116.

Cooperating with these electrodes is the main ercury electrode 117, whileadjacent to this electrode is the starting electrode 118 connected through a current-limiting device 119', to one of the supply mains. The

construction ofithe other rectifiers is the same as that of the'one described and therefore requires no further explanation. The

1 consumption circuit, which ist-o besupplied jointly by the rectlfiers, is represented by the mains'120 and 121,'between which translating devices .of any suitable character varied or otherwise, may be connected.

' Thus, for example, direct current .vapor lamps are indicated at 122, otherlamps at '123, a storagebattery at 124, a motor at 125, and soforth. One of the mains of the consumption circuit, 'as for example the main 121, is connected to the junction of the three inductance coils 126, 127 .and 128 "which are Y-connected-between the three supply mains 108, 109 and 110. The cores These electrodes are connected. across the supply mains as'clearly shown.

of these inductance coils may be separate, if desired, though I find that certain advantages, such .as saving in material, in economizing space and the like, may be secured by'mounting the coils on a single core asI have indicated in the drawing. This core consists of a number of legs connected by end pieces, -Three of the 'legs, as 129,

135 and 136. The system may be started up by the use of starting resistances in the same manner as described in connection w1th F1g. 3 but, for the purpose of avoiding unnecessary complication in the drawings, the illustration of such startin resistances, cooperating switches, and t e like,

has been omitted/ Fig. 9 difi'ers from Fig. 8 in that it represents .a number of rectifiers each fed from its own set of reactance coils as distinguished from the showing in Fig. 8 in which a plurality. of rectifiers are all fed in common from a singleset of inductance coils. Thus in Fig. 9 the two rectifiers 137 and 138, shown as representative of any desired number of rectifiers, cooperate respectively with the sets of Y-connected inductance coils 139 and 140. These inductance coils, unlike the set of inductance coils shown in Fig. 8, have separate cores. Otherwise than as described, the arrangement shown in Fig. 9 is the same as that shown in Fig. 8.

In Fig. 10 I have representedmy invention as applied to rectifiers of a form differing from those shown in previous figures of the drawing In Fig. 10 the source of current supply is represented as single phase and the supply system is such that a neutral conductor may be derived therefrom. For this purpose any one of a number of different arrangements may be utilized 'but by way of illustration I have represented a transformer having a primary 141 and a secondary 142. Mains 143 and 144 extend from the outside terminals of the secondary, and a neutral conductor 145 from a'point in the winding of intermediate potential. From these mains any number of rectifiers may be operated in multiple in accordance with my invention. In the drawings I have represented but two rectifiers, though it will be understood that any desired number may be used. These rectifiers are indicated at 146 and 147. Each rectifier consists as shownof an exhausted receptacle provided with a number of pockets containing-bodies of mercury constituting electrodes. In the rectivconsumption circuit leading to theneutral conductor 145. This consumption circuit may include translating devices-of any desired character suchqfor example as a storage battery 154, lamps 155, or the like. In shunt with these translating devices. is an inductance coil 156, the purpose of which is to causethe waves of current flowing in the rectifier or rectifiers' to lag more or less behind their electrp-motive forces. Under I these conditions an are always exists in the rectifier at the time the electro-motive force is passing through zero and as it commences to rise in the op site direction. The arc due to the preceding wavetherefore serves as a starting means for the succeeding wave, thereby maintaining the rectifier in operation. If a single rectifier alone is used, the inductance coil 156 in shunt to the load is all that is necessary to maintain the rectifier in operation.- When, however, a .number of rectifiers are to be operated in multiple, I connect in series with the lead extending from each tothe common load, an inductance coil indicated at 157 in the case of the rectifier 146 and at 158 inthe case of the rectifier 147. These inductance coilsprevent' the interference of each of the rectifiers with the other or others and enable the rectifiers to work together in parallel which they otherwise would be unable to do. Instead of the inductance coils 157 and 158 I may, if desired, substitute ohmic resistances.

In the fore oing descri tion-I have set forth in detai? 1 my invention may assume' in practice. It is to be understood, however, that many variations thereof may be niade without depart-' ing from the s irit of my invention, for which reason I o'not wish to be limited to the exact details shown and described. 7 i

What I claim as new and desire'to secure by Letters Patent of the United States, is,

1. .The combination of alternating current supply mains, inductance coils connected respectively to the supply mains and joined together at a'common point, and a plurality of vapor electric conductors having electrodes connected some to the supply mains and some in multipleto a circuit leading to said common point. I x

2. The combination of alternating current supply mains, a plurality of inductance coils connected to said mains and located on various em odiments which a single magnetic core, the magnetic circuit of one coil being non ldentical with that of another coil, and a vapor electric lamp or rectifier connected to said mains and to said inductance co1ls.

3. The combinatlon of a. vapor rectifier,

a load which is to be supplied with rectified.

current, a startin resistance, and a switch for connecting t e resistance first in cir-,

ode and a plurality of anodes, single phase supply mains, connections from the anodes of each envelop across said supply mains, a return conductor extending from said single phase system, and a circuit including an inductance, coil, extending from each cathode to said return conductor. Y

6.- The combination of a plurality of single phase rectifiers each provided with a plurality of anodes and acathode, a reactlurality of ex- 'hausted envelops each provi ed with a cathance in the direct current circuit of each rectifier, and connections for supplying the direct current of each rectifier to a common load and-for causing the direct current from each rectifierto') flow first through its own -reactance before passing to the common load.

7. The combination of a plurality of single phase rectifiers each having a cathode and a plurality of anodes, a reactance in the direct current circuit of each rectifier for producing an overlap in the current waves flowing in the rectifier, and a multiple connectionior the direct current circuits of the rectifiers joining these circuits together at that side of each'reactance ep-plosite the side connected to the cor'respon g rectifier.

8. The combination of 'a plurality of single phase vapor. electric devices each having a cathode] and a plurality, of anodes, a reactance connected to the cathode lead of each device, and a junctioii between the reactances such that each reactance is interposed between the junction and its corresponding cathode lead, whereby the arcs in each vapor device are caused to overlap and whereby the several vapordevices operate in multiple with each other. 4

9. The combination of a plurality of exhausted envelops each' provided .with a cathode and a plurality of anodes, single phase supply mains,; connections from-the anodes .of'each envelop across saidsupply f mains, a winding excitedgfrom said smgle base system, and a circuit including an inof each rectifier to a common load and for uctance coil, extendingfrom each cathode causing the direct current from each recti- U to ant-intermediate point on said Winding. fier to flow first through its own reactance' 10. The combination of a plurality of before passing to the common load. 5 single phase rectifiers each provided with a In Witness whereof, I have hereunto set 15 plurality of anodes and a cathode, a remy hand this 11th day of July, 1903.

actance in the direct current circuit of each SAMUEL FERGUSON; rectifier for producing an overlap in the cur- Witnesses: rent waves flowing in the rectifier, and con- BENJAMIN B. HULL,

10 nections for supplyingithe direct current HELEN ORFORD. 

